LANCASTER, Pa. — A young man accused of killing his 14-year-old girlfriend’s parents and running off with her pleaded guilty Wednesday to murder in a deal that spared him from the death penalty.

David G. Ludwig, 19, was sentenced to life in prison without parole for shooting Michael F. and Cathryn L. Borden inside their Lititz home in November after they demanded he break off his relationship with their daughter, Kara.

Ludwig and Kara had tried to keep their relationship secret from her parents, who were displeased with their age difference. Investigators said the Bordens confronted Ludwig after discovering he and Kara had been out all night.

After the talk, Ludwig used his father’s pistol to shoot the Bordens in the head, and Kara then climbed into his car and they set out to start a new life together out west, authorities said.

Investigators concluded that Kara joined Ludwig voluntarily but played no role in the shootings. She was not charged with a crime.

Prosecutors had been seeking the death penalty against Ludwig.

Ludwig had little to say in court as he pleaded guilty to charges that also included statutory sexual assault.

No apologyThe plea bargain bars Ludwig from speaking publicly about the case or profiting from it. District Attorney Don Totaro said the Borden family also asked that Ludwig not make a statement in court, not even to apologize.

“They thought it was a bit late for any sort of apology,” he said.

Kara was not in the courtroom. Her lawyer, Robert Beyer, said: “I think she’s happy to get this behind her and recapture her teenage years.”

They couple were caught a day after the killings, following an automobile chase that ended with Ludwig crashing his parents’ car into a tree in Indiana. Neither was hurt.

As for why Kara got into Ludwig’s car after he had killed her parents, Beyer said: “Kids make rash decisions under stress that are basically not understandable.”